When Abilities were introduced in Generation III, some Pokémon only had one possible Ability. A number of these species were given a second Ability in a later generation. If a Pokémon whose species gained an Ability after Generation III is transferred to Generations IV or V, it will initially retain its original Ability; upon evolving, however, its Ability slot will be recalculated and its Ability may change. When a Pokémon is transferred to Generation VI, however, it will be locked into the appropriate slot for its current Ability.

Which other pokémon gained a secondary ability in a later generation? This doesn't include hidden abilities. Only secondary abilities.